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* [Bug target/108790] New: bpf: gcc emits malformed ldxdw instruction at -O2 @ 2023-02-14 18:52 david.faust at oracle dot com 2023-02-14 22:47 ` [Bug target/108790] " cvs-commit at gcc dot gnu.org 2023-08-17 17:18 ` jemarch at gcc dot gnu.org 0 siblings, 2 replies; 3+ messages in thread From: david.faust at oracle dot com @ 2023-02-14 18:52 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108790 Bug ID: 108790 Summary: bpf: gcc emits malformed ldxdw instruction at -O2 Product: gcc Version: 13.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: target Assignee: unassigned at gcc dot gnu.org Reporter: david.faust at oracle dot com CC: cupertino.miranda at oracle dot com Target Milestone: --- Target: bpf With -O2 GCC emits a malformed ldxdw instruction in some cases: $ cat ldxdw.c unsigned long long test () { return *((unsigned long long *) 0x4000); } $ bpf-unknown-none-gcc -c -O2 ldxdw.c -o ldxdw.o /tmp/ccsuVj7l.s: Assembler messages: /tmp/ccsuVj7l.s:7: Error: unrecognized form of instruction `ldxdw %r0,16384' ldxdw (and all other {ldx,stx}{b,h,w,dw} insns should have a form like ldxdw %rX, [%rY + OFFSET] Looks like we need a better constraint on the memory operand in *mov<MM:mode>. Testing a patch for this now. ^ permalink raw reply [flat|nested] 3+ messages in thread
* [Bug target/108790] bpf: gcc emits malformed ldxdw instruction at -O2 2023-02-14 18:52 [Bug target/108790] New: bpf: gcc emits malformed ldxdw instruction at -O2 david.faust at oracle dot com @ 2023-02-14 22:47 ` cvs-commit at gcc dot gnu.org 2023-08-17 17:18 ` jemarch at gcc dot gnu.org 1 sibling, 0 replies; 3+ messages in thread From: cvs-commit at gcc dot gnu.org @ 2023-02-14 22:47 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108790 --- Comment #1 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by David Faust <dfaust@gcc.gnu.org>: https://gcc.gnu.org/g:c348a717213b03c6661878934f197f4d261f0e56 commit r13-5989-gc348a717213b03c6661878934f197f4d261f0e56 Author: David Faust <david.faust@oracle.com> Date: Tue Feb 14 11:23:01 2023 -0800 bpf: fix memory constraint of ldx/stx instructions [PR108790] In some cases where the target memory address for an ldx or stx instruction could be reduced to a constant, GCC could emit a malformed instruction like: ldxdw %r0,0 Rather than the expected form: ldxdw %rX, [%rY + OFFSET] This is due to the constraint allowing a const_int operand, which the output templates do not handle. Fix it by introducing a new memory constraint for the appropriate operands of these instructions, which is identical to 'm' except that it does not accept const_int. gcc/ PR target/108790 * config/bpf/constraints.md (q): New memory constraint. * config/bpf/bpf.md (zero_extendhidi2): Use it here. (zero_extendqidi2): Likewise. (zero_extendsidi2): Likewise. (*mov<MM:mode>): Likewise. gcc/testsuite/ PR target/108790 * gcc.target/bpf/ldxdw.c: New test. ^ permalink raw reply [flat|nested] 3+ messages in thread
* [Bug target/108790] bpf: gcc emits malformed ldxdw instruction at -O2 2023-02-14 18:52 [Bug target/108790] New: bpf: gcc emits malformed ldxdw instruction at -O2 david.faust at oracle dot com 2023-02-14 22:47 ` [Bug target/108790] " cvs-commit at gcc dot gnu.org @ 2023-08-17 17:18 ` jemarch at gcc dot gnu.org 1 sibling, 0 replies; 3+ messages in thread From: jemarch at gcc dot gnu.org @ 2023-08-17 17:18 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108790 Jose E. Marchesi <jemarch at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |RESOLVED Resolution|--- |FIXED CC| |jemarch at gcc dot gnu.org --- Comment #2 from Jose E. Marchesi <jemarch at gcc dot gnu.org> --- Fixed by the commit above. ^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2023-08-17 17:18 UTC | newest] Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2023-02-14 18:52 [Bug target/108790] New: bpf: gcc emits malformed ldxdw instruction at -O2 david.faust at oracle dot com 2023-02-14 22:47 ` [Bug target/108790] " cvs-commit at gcc dot gnu.org 2023-08-17 17:18 ` jemarch at gcc dot gnu.org
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